ASP.NET

Introduction
With the advent of ASP.NET we see a shift from traditional scripting to the
beginning of full-fledged programming online.VBScript isn’t the only option
anymore, as programmers can now employ the full power that lies behind both
Visual Basic (VB) and C within their ASP.NET assemblies.
There is no denying the widespread acceptance that .NET received from the
developer community. It’s proven itself to be a well-developed framework with
solid ideas on how the programming world should continue to change.The
introduction of a software solution that enables anyone to code in any language
that is compatible with the framework is groundbreaking to say the least.
In this chapter we will take a look at how Active Server Pages (ASP) itself
began just a couple of years ago and how it has captivated programmers ever
since. It has had some problems, of course, but the .NET architecture seems to
have found solutions to many preexisting programming problems.There have also
been changes with how ASP works with the server and client, to provide the user
with the information that you want to provide.
Even though this is a stable beta, and many people are assuming already that
what we are seeing within Beta 2 is basically the “freeze” for many features, it still
has a couple of caveats, due to its beta nature. Learning from these problems
within the framework can allow for preparation against it.
Learning from the History of ASP
You can trace the history of ASP right back to 1995 and the momentous occasion
when Microsoft realized they were falling behind in a fundamental shift in
the industry by not embracing the Internet. Up until that point Microsoft had
been developing their proprietary technologies, tools, and network protocols for
the Microsoft Network; all of a sudden they needed an Internet strategy and fast.
Microsoft has gone from a position of playing catch-up to one close to dominance,
with the Internet Explorer Web browser having a strangle-hold on the
Web browsing market, and Internet Information Server (IIS) installed at the
majority of Fortune 1000 companies.
The Origins of ASP
Back in the mid ‘90s, when the commercial Web world was still young, there was
not a great deal of choice of tools for the Web developer who wanted to make
his or her Web site a truly useful place to do business.The choices were limited
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in both available server-side programming platforms and also desktop development
tools to produce the solutions. In the end, the programmer was stuck with
clumsy Common Gateway Interface (CGI) programs using compiled languages
such as C, Delphi, and Visual Basic, or interpreted scripting languages like Perl or
Rexx, and operating system shell scripts on systems such as UNIX.
In early 1996 Microsoft had a first stab at improving the situation by
including the Internet Server Application Programming Interface (ISAPI) technology
as part of Internet Information Server. ISAPI is an extension to the
Windows Win32 API. It was developed as a way to create Web server software
that interacts with the inner workings of Internet Information Server, bringing
what was claimed to be a five-fold increase in performance. As you can well
imagine from this description, as well as the immediate performance increase, it
also had a side effect of increasing the complexity of the development for the
programmer. It wasn’t for the faint hearted, and it takes some serious hardcore
programming knowledge to do ISAPI applications right.As well as ISAPI,
Microsoft encouraged developers to embrace their Internet Database Connector
(IDC) technology.This was a new way to connect Web sites to back-end
databases through Open Database Connectivity (ODBC).
The ISAPI and IDC technologies lifted Microsoft’s youthful and as yet
unproven Web server from being a glorified file server to being a basic interactive
application server platform for the first time.
Other vendors had tools out there, and several were very popular, such as
Netscape Livewire. Livewire was a technology that ran under Netscape’s Web
server and used a version of JavaScript for page logic, and also used Java components.
Unfortunately, Livewire had similar limitations to ISAPI in that it was a
compiled technology and the server needed stopping and starting to make
changes visible.
Why ASP Was Needed
Not all Web developers have the programming skills needed to write ISAPI
applications, and because ISAPI requires the compilation of programs, there are
extra steps in producing an ISAPI-based site that slow development down.
Novice and intermediate programmers found the need to learn an industrialstrength
language, such as C++, and compile even the simplest of their page logic
into .dll files a real barrier.
Visual Basic programs, although easier to develop, when used for CGI, performed
poorly and the overhead hogged resources. Other languages such as Perl
require the Web server to launch a separate command-line program to interpret
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and execute the requested scripts, increasing page-load time and reducing server
performance. CGI itself hogs resources because every page request forces the Web
servers to launch and kill new processes and communicate across these processes.
This is time consuming and also uses up precious RAM.
Another problem facing development teams in the mid ‘90s was the fact that
a Web site is a mixture of Hypertext Markup Language (HTML) and logic.They
needed a way to mix the programmer’s code with the designer’s page-layout
HTML and designs without one messing up the other.There were many solutions
to this problem, ranging from custom template systems to Sever Side
Include (SSI) statements that told the server to execute code based on special
HTML comment tags.
Database-driven interactivity was another challenge.The demand for complex
Web sites had just kicked off, and developers needed to supply that demand in a
manageable fashion, but the tools available did not make this an easy task.Those
who could achieve it demanded rewards that matched the difficulty of what they
were being asked to do.
What was needed was a solution for the rest of us. It needed to be a simple
scripted text-based technology like Perl, so developers could tweak and alter their
pages without compilation and with simple text-editing tools such as Notepad. It
needed to have low resource requirements while keeping high performance;
therefore it needed to be executed within the server environment just like ISAPI,
but without the complexity. Designers and cross-discipline teams demanded that
it should include SSI and template features to make integrating page layouts simpler
to manage.To be truly popular, it should run off a language that would be
easy to pick up and was familiar to a large community of developers. Enter Active
Server Pages!
Why ASP Was Not Originally Embraced
Active Server Pages was not an overnight success, though understandably it did
capture the imagination of a large sector of the development community, particularly
those already well versed in Visual Basic programming or Visual Basic for
applications scripting.
Others who did not have an investment in Visual Basic knowledge found the
limitations of Visual Basic, and by extension Visual Basic Scripting, reasons to
avoid the technology. Faults included poor memory management, the lack of
strong string management abilities, such as Regular Expressions, found in other
established languages.When compared to CGI with Perl,ASP was found lacking.
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At that time, Internet Information Server was in its infancy, and take-up was
low, despite Microsoft’s public relations juggernaut going into full flow after the
company’s much-reported dramatic turnaround. In comparison to current versions
of the software it seems very poor, but it was still competitive on performance.
Until 1997, back-end Web programming was pretty much owned by CGI
and Perl. High-performance Web sites usually had a mix of C-compiled programs
for the real business engine, and Perl for the more lightweight form processing.
There was a fair amount of doubt and suspicion around Microsoft’s Internet
efforts, including IIS and Internet Explorer, and ISAPI had not done all that
much to bring across a huge sector of the development community. Despite this
uncertain atmosphere, Microsoft saw many Windows NT 4 licenses being bought
specifically for Web hosting and development increasing.Third-party support for
anything other than small components was initially slow, but, as with all Microsoft
products, after the first couple of releases they usually get things right, and ASP
was no exception.
Whereas Perl had a huge community of developers led by the heroic figure
of Larry Wall, the ASP developer was not yet well supported.A Perl programmer
was encouraged from the top to share and make his or her code open, so the
community thrived, with every conceivable solution or library just a few clicks
away at the Comprehensive Perl Archive Network (CPAN) site, or at one of the
many other Web sites and news groups. Contrast this with the ingrained competitive
and financially led philosophies of the third-party component vendors in the
Windows Distributed Internet Applications (DNA) world. Of course, it did not
take the ASP community long to grow to be the loving, sharing success it is now